2 research outputs found
Morphometric study of Acipenser nuccurii (Bonaparte, 1836) in fish farm individuals
The main objective of this study was to analyse differences and
similarities in morphometric characteristics among specimens of
the same year class of Acipenser naccarii (Bonaparte, 1836),
comparing fish raised either in Italy or Spain. All specimens were
F1 of captive broodstock in Italy.
Fifteen biometric variables were measured, and three derived
indices were calculated, on 30 individuals of 3+ year class from
Lombardy (Italy) and 90 individuals of I+, 2+ and 3+ year class
from Riofrio (Granada, Spain). A stepwise discriminate analysis
(SDA) was carried out, and the results were contrasted using a
non-hierarchical cluster analysis. The two groups proved to be
similar, so a principal component analysis and a simple
regression analysis were performed on all individuals, taking total
length (TI) as the independent variable and all the biometric
variables as dependent.
The study revealed that although the Soljan index (i.e. ratio of
mouth width to snout length) is related to TI, and is a valid
taxonomic characteristic, the CA index (i.e. relative position of
the barbels) and FB index (i.e. ratio of snout length to width) are also valid characteristics for individuals longer than 57 cm, being independent of TI
X-ray Photothermal Dosimetry With Optical Fibers
We propose an optical interforemetric sensor for X-ray dosimetry. The temperature rise DT produced in a silica optical fiber irradiated with chopped monochromatic X-rays indices a phase shift in the propagation of a He-Ne laser beam with respect to the unirradiated arm of interferometer. DT is proportional to the energy released in the fiber